Electric fans for radiators have been discussed extensively. If they are so good, don't you think OEM's would have been using them since they are easier to set up then a direct drive or a hydraulic drive and they take less horsepower drag? On big rigs, they had a setup that had 6-8 fans (depending on the radiator shape) and didn't work on a front radiator! Trying to get an electric motor that will pull like a 32" 8 bladed fan (the equivalent of 30hp) just won't happen. 30hp with a 24v electric motor would have to draw about 950 amps! With our side intake radiators, the only way to go is with either a direct drive or hydraulic motor setup. We've had too many members try electric and by now have realized that using an electric motor for the radiator is like banging your head against the wall because it feels so good. Good Luck, TomC
Tom, (and other anti-electric folks)
I have read just about all the old posts regarding electric fans (including some pretty heated ones with Twodoggs), and I hear you loud and clear. But please understand I'm in a difference situation: I'm not trying to take out the factory system and playing smart. I DO NOT HAVE A FACTORY SYSTEM TO START WITH! The engine and bay seems to have been altered, and I have a super-rare bus, which makes a engine driven fan almost impossible.
Hydraulics, as I'm quickly learning, is not cheap. I'd have to mount the pump on the passenger side, and use long hoses to reach the radiator. Even then, I'd have to play with altering pumps/motors, unless I find a 24" or smaller fan, unlikely on a transit.
Electric is simply one of the more viable options at this point. I'm not stuck on it, and I'm not saying it's superior, and I am not trying to argue, but electric is a possibility for me. If I do go electric, then no, I will not slap on some $35 Ebay fan.
Now, regarding the electric hp issue:
Important for us all to realize that cooling fan is not a "either you have the hp or you don't" thing. Any fluid (air) operates on a curve - flow, restriction, power, efficiency, heat conduction, etc.
I've looked at a lot of fan curves in the last couple days, and they all somewhat mirror what I've posted in that PDF - it takes a lot of hp to cover the max flow situation. As you increase flow over a set of fins, restriction goes up to the squared. Since power is a multiplication of flow and restriction, it goes up to the 3rd power.
You can get half the flow, and retain a huge amount of drivability, at only 1/8 the power. The problems with most "electric fans" on the web, is that they're most like 1/100 the power of a diesel engine fan. If I go electric, it will be the 1/8 to 1/4 power region, with a high voltage alternator setup. It will be an improvement over the current system, and though inadequate, has carried the PO across North America for 20+ years.
Regarding misters. I'll admit I'm not a big fan of them, and they do feel like a bandaid. However, after thinking about it, I don't think they are bad for the radiator at all. Think about driving in the rain with a front radiator. And doesn't matter where you live, the rain is guaranteed to be worse quality than potable water.